/*
 * @Copyright (c) 2018 缪聪(mcg-helper@qq.com)
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");  
 * you may not use this file except in compliance with the License.  
 * You may obtain a copy of the License at  
 *     
 *     http://www.apache.org/licenses/LICENSE-2.0  
 *     
 * Unless required by applicable law or agreed to in writing, software  
 * distributed under the License is distributed on an "AS IS" BASIS,  
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  
 * See the License for the specific language governing permissions and  
 * limitations under the License.
 */

package com.mcgrobot.plugin.endesign;

import java.io.ByteArrayOutputStream;
import java.security.InvalidKeyException;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class RSAEncrypt {
	
	private static Logger logger = LoggerFactory.getLogger(RSAEncrypt.class);
	private static String privateKey = "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";
	private static String publicKey = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCm83raeRgiS/FZfkzoxGKWDLREL8lS63S8JwJ6IYFIaRZjVSTV8xHHQUWB7F2qh1BbXg0LqAD8qqyYtIdNio8nksXcxlLhjvltw/iQ5EU1/kOg+ZpvUKWxRhjV+L+dN1mGGGS/JLRXEszdF4OxP7wTAaQvGVs+u6mwUFearrJYawIDAQAB";
	private static RSAPublicKey rsaPublicKey = loadPublicKeyByStr(publicKey);
	private static RSAPrivateKey rsaPrivateKey = loadPrivateKeyByStr(privateKey);
	
    /**
     * 字节数据转字符串专用集合
     */
    private static final char[] HEX_CHAR = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };

    public static void main(String[] args) throws Exception {
//    	System.out.println(genKeyPair());
  
    	String data = "TThis is a testasdfasfdasdfasdfasdfsafdsadfsd!";
   // 	String privateKey = "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";
    //	String publicKey = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCm83raeRgiS/FZfkzoxGKWDLREL8lS63S8JwJ6IYFIaRZjVSTV8xHHQUWB7F2qh1BbXg0LqAD8qqyYtIdNio8nksXcxlLhjvltw/iQ5EU1/kOg+ZpvUKWxRhjV+L+dN1mGGGS/JLRXEszdF4OxP7wTAaQvGVs+u6mwUFearrJYawIDAQAB";
    //	RSAPublicKey RSAPublicKey = loadPublicKeyByStr(publicKey);
    //	RSAPrivateKey RSAPrivateKey = loadPrivateKeyByStr(privateKey);
    	byte[] dataEncryptPut = encryptPub(data.getBytes());
        byte[] dataDecryptPri = decryptPri(dataEncryptPut); 	
    	
    	
    	System.out.println("----------" + segmentDecrypt("fXTbYbGZPr6bvVBmE3OsYptIdGRM9BtmV7kzirMdFYEB/TKIRENQdUXWAABnzyAZqcHw85PFipsFeIiRMmIlPJ3fiiovNdNOYeZsslyU/RZFkmbug1qziHkfhnFuKPm4wieAUUJ9pSlxk3ZcL8n3pVdduK0SnCoKJNgbK20gPEg="));
    	String result = new String(dataDecryptPri);
    	System.out.println(result);
    	
    	String newData = "okcctv";
    	byte[] dataEncryptPri = encryptPri( newData.getBytes());
    	byte[] dataDecryptPub = decryptPub( dataEncryptPri);
    	
    	System.out.println(new String(dataDecryptPub));
    	
	}
    public static String segmentDecrypt(String data) throws Exception {
    	String result = "";
    	String[] str = data.split(",");
		if(str !=null && str.length > 0) {
			
			int inputLen = str.length;
	        ByteArrayOutputStream out = new ByteArrayOutputStream();
	        byte[] cache;
	        int i = 0;
	        try {
		        // 对数据分段解密
		        while (inputLen - 1 >= 0) {
		        	byte[] bt = Base64.decode(str[i]);
		    		Cipher cipher = Cipher.getInstance("RSA");
		    	    cipher.init(Cipher.DECRYPT_MODE, rsaPrivateKey);
		    	    cache = cipher.doFinal(bt);
		            out.write(cache, 0, cache.length);
		            i++;
		            inputLen--;
		        }
	        
		        byte[] decryptedData = out.toByteArray();
	        
		        result = new String(decryptedData);
			} catch (Exception e) {
				logger.error("分段解密出错：", e);
			} finally {
				if(out != null) {
					out.close();
				}
			}
		}
		return result;
    }
    
    /**
     * 随机生成密钥对
     */
    public static String genKeyPair() {
        // KeyPairGenerator类用于生成公钥和私钥对，基于RSA算法生成对象
        KeyPairGenerator keyPairGen = null;
        try {
            keyPairGen = KeyPairGenerator.getInstance("RSA");
        } catch (NoSuchAlgorithmException e) {
        	logger.error("genKeyPair() ", e);
        }
        // 初始化密钥对生成器，密钥大小为96-2048位
        keyPairGen.initialize(1024, new SecureRandom());
        // 生成一个密钥对，保存在keyPair中
        KeyPair keyPair = keyPairGen.generateKeyPair();
        // 得到私钥
        RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
        // 得到公钥
        RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
        // 得到公钥字符串
        String publicKeyString = Base64.encode(publicKey.getEncoded());
        // 得到私钥字符串
        String privateKeyString = Base64.encode(privateKey.getEncoded());
        // 将密钥对写入到文件
        return "{publicKey:" + publicKeyString + ", privateKey:" + privateKeyString + "}";
    }

    /**
     * 从字符串中加载公钥
     * 
     * @param publicKeyStr 公钥数据字符串
     * @throws Exception 加载公钥时产生的异常
     */
    public static RSAPublicKey loadPublicKeyByStr(String publicKeyStr) {
        try {
            byte[] buffer = Base64.decode(publicKeyStr);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            X509EncodedKeySpec keySpec = new X509EncodedKeySpec(buffer);
            return (RSAPublicKey) keyFactory.generatePublic(keySpec);
        } catch (NoSuchAlgorithmException e) {
        	logger.error("无此算法，异常信息：", e);
        } catch (InvalidKeySpecException e) {
        	logger.error("公钥非法，异常信息：", e);
        } catch (NullPointerException e) {
        	logger.error("公钥数据为空，异常信息：", e);
        } 
        return null;
    }

    public static RSAPrivateKey loadPrivateKeyByStr(String privateKeyStr) {
        try {
            byte[] buffer = Base64.decode(privateKeyStr);
            PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(buffer);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            return (RSAPrivateKey) keyFactory.generatePrivate(keySpec);
        } catch (NoSuchAlgorithmException e) {
        	logger.error("无此算法，异常信息：", e);
        } catch (InvalidKeySpecException e) {
        	logger.error("私钥非法，异常信息：", e);
        } catch (NullPointerException e) {
        	logger.error("私钥数据为空，异常信息：", e);
        }
        return null;
    }

    private static String encryptByPublicKey(String plainText) throws Exception {
    	  int MAX_ENCRYPT_BLOCK = 128;
    	  byte[] data = plainText.getBytes("utf-8");
    	 
    	  // 对数据加密
    	  Cipher cipher = Cipher.getInstance("RSA");
    	  cipher.init(Cipher.ENCRYPT_MODE, rsaPublicKey);
    	  int inputLen = data.length;
    	  ByteArrayOutputStream out = new ByteArrayOutputStream();
    	  int offSet = 0;
    	  byte[] cache;
    	  int i = 0;
    	  try {
    	  // 对数据分段加密
    	  while (inputLen - offSet > 0) {
    	    if (inputLen - offSet > MAX_ENCRYPT_BLOCK) {
    	      cache = cipher.doFinal(data, offSet, MAX_ENCRYPT_BLOCK);
    	    } else {
    	      cache = cipher.doFinal(data, offSet, inputLen - offSet);
    	    }
    	    out.write(cache, 0, cache.length);
    	    i++;
    	    offSet = i * MAX_ENCRYPT_BLOCK;
    	  }
    	  byte[] encryptedData = out.toByteArray();
    	  return Base64.encode(encryptedData);
    	  
    	  } catch (Exception e) {
			logger.error("", e);
    	  } finally {
			if(out != null) {
				out.close();
			}
    	  }
    	  return null;
    	}
    
    
    /**
     * 公钥加密过程
     * 
     * @param publicKey 公钥
     * @param plainTextData 明文数据
     * @return
     * @throws Exception 加密过程中的异常信息
     */
    public static byte[] encryptPub(byte[] plainTextData) throws Exception {
        if (publicKey == null) {
            throw new Exception("加密公钥为空, 请设置");
        }
        Cipher cipher = null;
        try {
            // 使用默认RSA
            cipher = Cipher.getInstance("RSA");
            // cipher= Cipher.getInstance("RSA", new BouncyCastleProvider());
            cipher.init(Cipher.ENCRYPT_MODE, rsaPublicKey);
            byte[] output = cipher.doFinal(plainTextData);
            return output;
        } catch (NoSuchAlgorithmException e) {
        	logger.error("无此加密算法，异常信息：{}", e);
            throw new Exception("无此加密算法");
        } catch (NoSuchPaddingException e) {
        	logger.error("NoSuchPaddingException ", e);
            return null;
        } catch (InvalidKeyException e) {
        	logger.error("加密公钥非法，异常信息：{}", e);
            throw new Exception("加密公钥非法,请检查");
        } catch (IllegalBlockSizeException e) {
        	logger.error("明文长度非法，异常信息：{}", e);
            throw new Exception("明文长度非法");
        } catch (BadPaddingException e) {
        	logger.error("明文数据已损坏，异常信息：{}", e);
            throw new Exception("明文数据已损坏");
        }
    }

    /**
     * 私钥加密过程
     * 
     * @param privateKey 私钥
     * @param plainTextData 明文数据
     * @return
     * @throws Exception 加密过程中的异常信息
     */
    public static byte[] encryptPri(byte[] plainTextData) throws Exception {
        if (privateKey == null) {
            throw new Exception("加密私钥为空, 请设置");
        }
        Cipher cipher = null;
        try {
            // 使用默认RSA
            cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.ENCRYPT_MODE, rsaPrivateKey);
            byte[] output = cipher.doFinal(plainTextData);
            return output;
        } catch (NoSuchAlgorithmException e) {
        	logger.error("无此加密算法，异常信息：{}", e);
            throw new Exception("无此加密算法");
        } catch (NoSuchPaddingException e) {
        	logger.error("NoSuchPaddingException  ", e);
            return null;
        } catch (InvalidKeyException e) {
        	logger.error("加密私钥非法，异常信息：{}", e);
            throw new Exception("加密私钥非法,请检查");
        } catch (IllegalBlockSizeException e) {
        	logger.error("明文长度非法，异常信息：{}", e);
            throw new Exception("明文长度非法");
        } catch (BadPaddingException e) {
        	logger.error("明文数据已损坏，异常信息：{}", e);
            throw new Exception("明文数据已损坏");
        }
    }

    /**
     * 私钥解密过程
     * 
     * @param privateKey 私钥
     * @param cipherData 密文数据
     * @return 明文
     * @throws Exception 解密过程中的异常信息
     */
    public static byte[] decryptPri(byte[] cipherData) throws Exception {
        if (privateKey == null) {
            throw new Exception("解密私钥为空, 请设置");
        }
        Cipher cipher = null;
        try {
            // 使用默认RSA
            cipher = Cipher.getInstance("RSA");
            // cipher= Cipher.getInstance("RSA", new BouncyCastleProvider());
            cipher.init(Cipher.DECRYPT_MODE, rsaPrivateKey);
            byte[] output = cipher.doFinal(cipherData);
            return output;
        } catch (NoSuchAlgorithmException e) {
        	logger.error("无此解密算法，异常信息：{}", e);
            throw new Exception("无此解密算法");
        } catch (NoSuchPaddingException e) {
        	logger.error("NoSuchPaddingException  ", e);
            return null;
        } catch (InvalidKeyException e) {
        	logger.error("解密私钥非法，异常信息：{}", e);
            throw new Exception("解密私钥非法,请检查");
        } catch (IllegalBlockSizeException e) {
        	logger.error("密文长度非法，异常信息：{}", e);
            throw new Exception("密文长度非法");
        } catch (BadPaddingException e) {
        	logger.error("密文数据已损坏，异常信息：{}", e);
            throw new Exception("密文数据已损坏");
        }
    }

    /**
     * 公钥解密过程
     * 
     * @param publicKey 公钥
     * @param cipherData 密文数据
     * @return 明文
     * @throws Exception 解密过程中的异常信息
     */
    public static byte[] decryptPub(byte[] cipherData) throws Exception {
        if (publicKey == null) {
            throw new Exception("解密公钥为空, 请设置");
        }
        Cipher cipher = null;
        try {
            // 使用默认RSA
            cipher = Cipher.getInstance("RSA");
            // cipher= Cipher.getInstance("RSA", new BouncyCastleProvider());
            cipher.init(Cipher.DECRYPT_MODE, rsaPublicKey);
            byte[] output = cipher.doFinal(cipherData);
            return output;
        } catch (NoSuchAlgorithmException e) {
        	logger.error("无此解密算法，异常信息：{}", e);
            throw new Exception("无此解密算法");
        } catch (NoSuchPaddingException e) {
        	logger.error("NoSuchPaddingException  ", e);
            return null;
        } catch (InvalidKeyException e) {
        	logger.error("解密公钥非法，异常信息：{}", e);
            throw new Exception("解密公钥非法,请检查");
        } catch (IllegalBlockSizeException e) {
        	logger.error("密文长度非法，异常信息：{}", e);
            throw new Exception("密文长度非法");
        } catch (BadPaddingException e) {
        	logger.error("密文数据已损坏，异常信息：{}", e);
            throw new Exception("密文数据已损坏");
        }
    }
    
    
    /**
     * 字节数据转十六进制字符串
     * 
     * @param data 输入数据
     * @return 十六进制内容
     */
    public static String byteArrayToString(byte[] data) {
        StringBuilder stringBuilder = new StringBuilder();
        for (int i = 0; i < data.length; i++) {
            // 取出字节的高四位 作为索引得到相应的十六进制标识符 注意无符号右移
            stringBuilder.append(HEX_CHAR[(data[i] & 0xf0) >>> 4]);
            // 取出字节的低四位 作为索引得到相应的十六进制标识符
            stringBuilder.append(HEX_CHAR[(data[i] & 0x0f)]);
            if (i < data.length - 1) {
                stringBuilder.append(' ');
            }
        }
        return stringBuilder.toString();
    }
    

}
